Do you believe in hypnosis? Maybe you’ve heard of those tapes that promise to help you lose weight or stop smoking, or cure all your fears, or help you remember a past life. Maybe you’re more familiar with stage hypnosis, the kind where a magician makes an unsuspecting audience member cluck and peck about the stage like a chicken. Or maybe you remember the recent case of a principal who was found responsible for the deaths of three students he’d hypnotized. Maybe you’re skeptical; maybe you’re a believer.

Hypnosis has always been somewhat controversial. According to Dr. David Patterson, a University of Washington professor and hypnosis practitioner, though, “Hypnosis is a true perceptual phenomenon that allows people to do remarkable things when used in the right circumstances, and it has accrued a surprising amount of scientific support over the last few years.” He suggests it can be a powerful therapeutic tool, and the American Psychological Association (APA) endorses it as a technique for treating conditions like anxiety. He also says, however, that it’s “a type of intervention that has always catered to people that are a bit on the edge.”

That type of intervention is no longer limited to professional use or those audiotapes you used to see advertised on late-night TV. It’s now available in the palm of your hand, thanks to any number of smartphone apps you can download, probably for free. And those apps—a search for “hypnosis” in Apple’s App Store yields 1,140 results—are among the many that promise health benefits, often with little to no evidence supporting their assertions. It’s a large-scale problem, and one that standard regulations may not be able to alleviate.

Let’s stick to hypnosis for now. In 2014, a team of researchers reviewed 1,455 hypnosis apps in the App Store and found not a single one “reported having been tested for efficacy, and none reported being evidence-based.” Their study indicates only 7 percent of hypnosis apps listed in the App Store even mentioned the developer’s medical credentials. “At best, apps not supported by empirical evidence are misleading, at worst, unethical,” they wrote in their report. The team recognized hypnosis apps have potential but ultimately need scrutiny.

“Hypnosis is a true perceptual phenomenon that allows people to do remarkable things when used in the right circumstances.”

The apps make alluring (if familiar) promises: You can lose weight, quit smoking, cure your insomnia, ADHD, agoraphobia, and alcoholism. Some even claim to perform past life regression—would you like to remember your past incarnations? Many users don’t seem to mind the lack of evidence. “Words cannot describe how I feel since using this app,” writes one iPhone user in the reviews for the Law of Attraction Hypnosis app. “It was amazing, and like nothing I’ve ever experienced,” writes another user of the app Past Life Regression Hypnosis (rated for ages 4 and up). “It felt like magic.”

Not all experiences are positive, though. “I’m not 100% certain what to say here,” another user writes of the same app. “But halfway through I just had the worst feeling ever, like I was sinking and got really nauseous. I had to stop. That was over an hour ago and I still don’t feel right. Sluggish, disconnected somehow.” Other reviewers echo this sentiment: “I stopped it in the middle because I felt as if I was being taken over. I felt negative energy entering my body. I deleted it immediately. I feel different. As if someone else is in control. I don’t feel normal.”

The reviews suggest that many users experience something, whether good or bad. That’s not surprising to Dr. Elgan Baker, psychiatry professor at Indiana University and former director of the Indiana Center for Psychoanalysis. He’s long worked in hypnotherapy and cautions against taking it lightly. “Self-hypnosis without a trained professional is not a good idea. Self-appendectomy is not a good idea. Self–C-section is not a good idea,” he says. Hypnosis, he says, often brings “repressed trauma and painful emotions to the surface in a way which causes regression or retraumatization” and the “development of pathological behaviors and ideas.” That’s why he considers apps, convenient as they are, a poor substitute for professional hypnotherapy. For one thing, an app can’t detect or monitor these side effects.

Dr. Patterson is more sanguine: “Audiotaped versions of hypnosis have been around for years and I do not see an app as any different than them.” However, he says, “It is frustrating to a scientist that a couple of people will end up making a lot of money on apps when it does not take that much knowledge or training in hypnosis to create a product to sell to the public.” At the same time, he doesn’t see those apps as a threat to legitimate, practicing hypnotherapists, because they’re based on faulty science. “Hypnosis apps are largely a matter of lay hypnotists trying to make money.”

“Self-hypnosis without a trained professional is not a good idea. Self-appendectomy is not a good idea. Self–C-section is not a good idea.”

Even so, should they be more closely regulated, either by laws or by the companies running the app stores? Who’s responsible for the user who wrote “I don’t feel normal” after using a hypnosis app?

Hypnosis is largely unregulated. In the U.S., only nine states have specific guidelines that monitor and license practitioners. (That Florida principal ultimately pleaded no contest to practicing therapeutic hypnosis without a license, serving a year’s probation.) Internationally, Australia bans potentially hypnotic messages from broadcast. But governmental definitions of “hypnosis” vary and create inconsistent legislation. Some consider it a type of therapy, requiring licensing, while others do not. Meanwhile, groups like the Society of Psychological Hypnosis try to educate the public to ensure no one undergoes hypnosis without a licensed medical professional.

So it’s unclear how limited state guidelines would apply to hypnosis apps. At the federal level, things aren’t much clearer. Two federal agencies would likely have jurisdiction: the Federal Trade Commission (FTC) and the Food and Drug Administration (FDA). In September, the FTC took on an app called Ultimeyes, which promised to improve users’ vision. Jessica Rich, director of the Bureau of Consumer Protection at the FTC, vowed that “the FTC will not hesitate to act when health-related claims are not based on sound science.” But it remains to be seen how often the FTC will intervene, or how stringently it will define “sound science.”

After years of controversy, the FDA recently issued its ruling on mobile medical apps. It promised regulation on apps that may impact the performance or functionality of currently regulated medical devices or those that may pose a risk to patients if they don’t work as intended. The FDA explicitly does not regulate apps that “help patients with diagnosed psychiatric conditions … maintain their behavioral coping skills by providing … audio messages that the user can access when experiencing increased anxiety.” Apps that “provide daily motivational tips (e.g., via text or other types of messaging)” will also go unregulated.

“I stopped it in the middle because I felt as if I was being taken over. I don’t feel normal.”

So the FDA has largely abdicated from a strong regulatory role. Apple’s developer guidelines provide some protection for users, forbidding “[a]pps that provide diagnoses, treatment advice, or control hardware designed to diagnose or treat medical conditions that do not provide written regulatory approval upon request.” But a look at the App Store’s contents calls into question how often Apple actually requests regulatory approval on such apps and where it, too, has drawn the line between illness monitoring and treatment.

What’s keeping the FDA from stronger regulation? One answer may be Apple itself: While the company has increased lobbying efforts in the last decade, it only lobbied the FDA in 2012, 2014, and 2015, years when the agency negotiated medical app policies. In a 2014 FDA meeting, Apple saw “mobile technology platforms as an opportunity for people to learn about themselves.” It felt an “opportunity to do more with devices, and that there may be a moral obligation to do more.” With the growing popularity of wearable health tech, Apple stands to profit from loose app regulation.

But who lobbies in the opposite direction? The American Psychological Association is a powerful mental health advocate, but it does not lobby the FDA or the FTC, which has the power to remove apps based on false marketing claims. And in light of the APA’s recent lobbying scandal and the ensuing $9 million settlement, it’s difficult to say if the organization will be gun-shy on the matter.

Ultimately, it seems that the FDA and FTC largely agree with Dr. Patterson, who compares hypnosis apps to audio tapes or self-help books. “There may be some benefits but they will seldom compare to going to [a] licensed healthcare professional,” he says. And for now, weighing risks and benefits is almost entirely up to the people who choose to use these apps.